All exposed stainless steel surfaces should be wiped with a clean cloth and warm water using a medium Ph detergent, frequently creating a routine.
For dirty or stained surfaces, abrasive powders or suspensions may be used that do not scratch surfaces, such as household cleaners. They can be used with hot water, soft brushes, clean sponges or cloths. For a more active cleaning a small amount of added vinegar to these powders will increase the success rate.
Carbon brushes and steel strips (such as metal sponges for dishes) should be avoided, as they can leave particles incorporated into the surface, which will lead to rusting over time.
Any surface cleaning should always be immediately followed by rinsing, to remove traces of detergent with warm water and then clean thoroughly with a dry towel.
It is recommended that routine cleaning operations be carried out at least twice a month for objects used occasionally and more frequently in areas where heavy or frequent use may occur.
Stainless Steel - Cleaning, care and maintenance
The attractive surface appearance and hygiene of stainless steel products can not be considered as completely maintenance-free. All surface qualities and finishes for stainless steels may actually stain, discolour or cover with a dirt-adhering layer during normal use. To obtain the maximum corrosion resistance on the stainless steel surface they must be kept clean.
Provided that the material type and surface finishing are correctly selected according to the environmental conditions, the manufacturing and installation procedures have been correct and that the cleaning programs are carried out regularly, good performance will be achieved and a longer service life. Frequency and cost of cleaning for stainless steel is lower than for many other materials and this often weighs in making the decision to accept higher acquisition costs.
Why maintenance is needed
Surface contamination and the formation of dirt or lime deposits are critical factors that can lead to a drastically reduced lifetime for stainless steels. These contaminants can be tiny iron or rust particles from other non-stainless steels used nearby or left on the surface and not later removed. In use in industrial, commercial and even domestic use conditions naturally atmospheric conditions can lead to the formation of dirt deposits or other nature, which can be quite corrosive. An example is the use of salt in kitchen or salt water when used in marine environments.
Working environments can also create more aggressive conditions, such as warm atmosphere in professional kitchens, high humidity, covered swimming pools. These environments can increase corrosion speed and therefore require maintenance, more frequent. Modern processes use cleaners, sterilizers and bleaches for cleaning and hygiene. All these solutions have the property, when used in accordance with their instructions, to achieve the intended purpose. However, if used incorrectly (eg under temperature and concentration conditions other than those recommended by the manufacturer), they may cause surface changes and corrosion made of stainless steel.
Strong acidic solutions (for example, hydrochloric acid or salts thereof) are sometimes used to clean masonry and wall cladding in building environments, but should not be allowed to come into contact with metals, including stainless steel. If this occurs acidically, the contaminant solution should be removed immediately by thoroughly washing with clean water.
Maintenance during installation
Cleaning of new products should not pose any particular problem, although more attention may be needed if the period elapsed between delivery and installation has been prolonged. If surface contamination is suspected, an immediate cleaning will remove the cause and result in a seamless service life for stainless steel objects.
Maintenance during use
The advice of the specialists is, even if the frequency of cleaning stainless steel products is your request and requires some costs to be done. The motivation is quite simple: "A metal should be cleaned when it is dirty to render the original look." This range may vary from one to four times a year for domestic applications or public spaces, or it may be once a day for situations where hygiene conditions are an element of activity, mandatory, or the environment in which the activity is carried out. aggressive. In many applications, the cleaning frequency is after each use.
Measures to prevent contamination during manufacture
Stainless steels can be contaminated by contact with carbon steel elements ("free iron") and this can quickly lead to the development of corrosion points. Ideal is to have dedicated workshops and machines with active elements in stainless steel.
In a workshop for the processing of stainless steels, it is also advisable to avoid contamination by knocking or rubbing with:
• Metal hand tools or used for the processing of other metals;
• Abrasive discs, wire brushes, belts
• Carbon steel storage racks;
• Contamination with filing or sparks from welding gives out the disk drives;
• Handling equipment (forklifts, cranes, hoists, pliers, etc.);
• Storage in areas adjacent to the production of carbon steel products.
Stainless steel is easy to clean. Washing with soap or detergent and hot water followed by a clean water rinse is usually quite suitable for household and architectural equipment. An improved look will be achieved if the surface is cleaned and then dried and dried. Specific cleaning methods are the same as in Table 1.
In the following section we recommend some passivation treatments for removing free iron and other contaminants resulting from handling, manufacturing, or exposure to contaminated atmospheres, as well as pickling treatments to remove stains that may occur at elevated temperatures through thermal influences) in treatment operations thermal or welding.
Table 1. Methods for Cleaning Stainless Steel
Problem Surface finishing quality Cleaning agent Remarks and comments
Routine cleaning All aggressive soaps or detergents and water (preferably warm) Sponge, rinse with clean water, dry if necessary. Follow the surface finishing lines.
Handwriting fingerprints All Soap or detergent and hot water or organic solvent (eg ethyl alcohol, acetone, methyl alcohol), rinse with clean, dry water. Keep the surface finishing lines.
Persistent stains and color changes All Aggressive Medium Cleaner Solutions, for example CIF (not for stainless steel) Use soft, natural or natural nylon cloth, sponge or brush. An old toothbrush can be useful. Rinse thoroughly with clean water and dry
Deposits of limestone from the hard water All Solution of vinegar part to three parts of water Blend in the solution a brush, then brush the surface to remove the deposits. Rinse thoroughly with clean water and dry
Oil or grease stains All Organic solvents (eg acetone, ethyl alcohol, methyl alcohol) Grease stains on pastry pots can be pre-soaked with ammonia Wash with soap or detergent. Rinse with clean, dry water. Fill the surface finishing lines.
Rust and other corrosion products by contamination All rust stains can be removed by adding a portion of nitric acid to nine parts of hot water. Leave to act for 30-60 minutes, then wash with plenty of water (washing will not be done in basins but only with water jet). See also the previous passive section. Rinse thoroughly with clean water. Wear rubber gloves, mix the solution in a glass container. Increased attention to acid handling.
Routine cleaning of boat reinforcements All Frequent washing with fresh water is recommended for "fresh" water washing every time the boat is used in salt water
Dishes (pots, crates, etc.) for cooking All Remove the traces of cooked food by soaking it in warm water with detergent, sodium bicarbonate or ammonia. Then clean and polish the surface with a light abrasive if necessary. See steel wool comments
Surface oxidation (staining) resulting from welding or heat treatment All pickling solutions according to the chapter "Pickling Treatments" Rinse thoroughly with clean water. Wear rubber gloves, mix the solution in a glass container. Increased attention to handling acid solutions.
Scratch Finish "Satin" or "Scotch Brite" Light scratches - use impregnated nylon sponges. Deeper scratches - sand the surface with iron-free abrasives Follow the surface finishing lines. Spray with soapy or medium-aggressive detergents and water (preferably warm) Do not use ordinary wire sponge particles can remain impregnated to the surface and there will be rusting problems after the process. The stainless steel wire and the "Scotch brite" type are acceptable.
Acids should only be handled using gloves and safety glasses. Care must be taken to ensure that acids or their solutions are not discharged over adjacent areas. All residues must be cleaned periodically in a waste treatment stream. Always dilute by adding acid to water, not water to acid. Use acid-resistant containers such as glass or plastic. If surface maturing can not be tolerated, a surface remediation treatment process should be performed; in particular for pickling operations. All treatments should be followed by water jet rinsing.
Solvents should not be used in enclosed spaces. Smoking and open fire should be avoided when using solvents
Chlorides are present in many cleaning agents. If the cleaning agent used contains chlorides, discolorants, bleaches or hypochlorites, then it must be thoroughly cleaned by washing and rinsing with clean water.